$btn-gr:#31c27c;
$theme-color:#31c27c;
@mixin btn-base($w:200px, $h:72px, $fz:28px) {
  display: inline-block;
  width: $w;
  height: $h;
  line-height: $h;
  @include font-dpr($fz);
  text-align: center;
  -webkit-border-radius: 4px;
  -moz-border-radius: 4px;
  border-radius: 4px;
}

@mixin font-dpr($font-size) {
  font-size: $font-size;
  [data-dpr="2"] & {
    font-size: $font-size * 2;
  }
  [data-dpr="3"] & {
    font-size: $font-size * 3;
  }
}


